Thin film strips

ABSTRACT

A method of forming a thin film strip and thin film strips formed thereby where the method comprises coating a liner substrate with a wet slurry of film forming ingredients and other components and drying the wet slurry in a drying apparatus to form a film, measuring the moisture content of the film either during of upon exit from the drying apparatus, and storing the film in a minimal moisture loss environment during a curing process.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of, and claims priority to, U.S. patentapplication Ser. No. 10/922,502, filed on Aug. 20, 2004, now allowed,which claims benefit to U.S. application Ser. No. 10/226,451, filed onAug. 23, 2002, now issued.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention is generally related to the processing of thinfilms, and in particular to the formation of coated film strips. Morespecifically, it relates to water soluble coated film strips and toedible water soluble thin film strips.

SUMMARY OF THE INVENTION

The present invention is directed to methods of forming thin film stripsand to strips formed by such methods. In one embodiment the methodcomprises coating a liner substrate with a wet slurry of film formingingredients and drying the wet slurry to form a film. Since many filmforming systems require the removal of some but not all the moisture inthe film, the moisture content of the film is monitored during and/orafter drying under conditions that are varied to meet the moisturecontent requirements of the film being produced. After exiting from thedrying operation, the film is stored in a controlled environment where,during a curing process, the moisture content is maintained or modifiedto reach the desired level of moisture in the finished product.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the present invention areexplained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 is a schematic diagram of a system incorporating features of thepresent invention.

FIG. 2 is a side view of a substrate coated with a film forming slurryin the system illustrated in FIG. 1.

FIG. 3 is a side view of a portion of the cutting process in a systemincorporating features of the present invention.

FIG. 4 is a top plan view of a cutting mechanism for a systemincorporating features of the present invention.

FIG. 5 is a side view of one embodiment of the converting process inaccordance with features of the present invention.

FIG. 6 is a side view of one embodiment of the converter system in athin film manufacturing process incorporating features of the presentinvention.

FIG. 7 is a top view of the system illustrated in FIG. 6.

FIG. 8 is an end view of the system illustrated in FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

Referring to FIG. 1, a schematic diagram of a system 10 incorporatingfeatures of the present invention is illustrated. Although the presentinvention will be described with reference to the embodiment shown inthe drawings, it should be understood that the present invention can beembodied in many alternate forms of embodiments. In addition, anysuitable size, shape or type of elements or materials could be used.

As shown in FIG. 1, the system 10 is generally adapted to coat, dry andcut a relatively thin film forming material 12 into small strips 8.Preferably, each strip 8 of thin film 12 is approximately 1 inch×1 inch(2.54 cm×2.54 cm), although any suitable dimensions can be used.

Water soluble films, particularly orally edible films can include manyingredients. The base ingredients for forming a film may include water,which can be later partially or completely dried out of the film, and afilm forming agent. The film may include additives for purposes ofpromoting the integrity of the film, plasticizing, stabilizing,emulsifying, filling thickening, or binding the film.

The film can be used as a delivery system for agents that do notnecessarily increase the functionality of the film but which provide abenefit to the user.

The formed film 12 is generally a thin, dissolvable film. In oneembodiment, the formed film 12 is adapted to be an edible film for oralintake and use, such as saliva stimulating agents, cooling agents,flavorants, coloring agents, sweeteners, fragrances, for the purpose ofbreath freshening, oral hygiene, and dispensing of medicaments andnutraceuticals

In another embodiment, the thin, dissolvable film comprises water, asoluble polymer and a cosmetic or skin care product incorporated withinthe polymer matrix.

Where the film forming, water soluble polymer is water soluble it may becomposed of, but is not limited to polymers selected from pullulan,hydroxypropylmethyl cellulose, hydroxyethyl cellulose, hydroxypropylcellulose, polyvinyl pyrrolidone, carboxymethyl cellulose, polyvinylalcohol, sodium alginate, polyethylene glycol, pectin, tragacanth gum,guar gum, acacia gum, Arabic gum, polyacrylic acid, methylmethacrylatecopolymer, carboxyvinyl polymer, gelatin, amylase, high amylase starch,hydroxypropylated high amylase starch, dextrin, chitin, chitosan, levan,elsinan, collagen, zein, gluten, soy protein isolate, whey proteinisolate, casein and mixtures thereof.

Recognized film-forming agents include, xanthan gum, polysaccharides,natural gums, polypeptides, polyacrylates, starch, karaya gum, mixturesthereof and others.

Other film forming agents which can be used include, but are not limitedto, cellulose ethers; modified starches; natural gums; edible polymers;hydrocolloid flours; seaweed extracts; land plant extracts; derivativesthereof; and combinations thereof.

Examples of cellulose ethers include, but are not limited to,methylcellulose, ethylcellulose, hydroxymethylcellulose,hydroxyethylcellulose, hydroxypropylmethylcellulose,carboxymethylcellulose, derivatives thereof and combinations thereof.

Modified starch examples include, but are not limited to, acid andenzyme hydrolyzed corn and potato starches. Further examples of naturalgums include, but are not limited to, gum arabic; locust bean gum;carageenan gum; karaya; ghatti; tragacanth agar; tamarind gum; xanthangum; derivatives thereof; and combinations thereof.

Examples of edible polymers include, but are not limited to,microcrystalline cellulose; cellulose ethers; xanthan; derivativesthereof; and combinations thereof. Examples of hydrocolloid flourinclude, but are not limited to, guar gum; locust bean; microcrystallinecellulose; tara; derivatives thereof and combinations thereof.

Seaweed extract examples include, but are not limited to, alginates;carageenans; derivatives thereof; and combinations thereof. Land plantextract examples include, but are not limited to, konjac; pectin;arabinogalactan; derivatives thereof; and combinations thereof.

It should be appreciated by those skilled in the art, that there areother edible water-soluble film forming agents which exhibit desirableproperties.

Preferred film forming water soluble polymers are pullulan,hydroxypropylethyl cellulose, hydroxyethyl cellulose, hydroxypropylcellulose, carboxymethyl cellulose, sodium alginate, pectin, andmixtures thereof.

The most preferred film forming water-soluble polymers are pullulan,pectin, and mixtures thereof.

In general, the effective amount of the film forming agent ranges fromapproximately about 10% to about 90%, more preferably 25% to about 75%dry weight of the film composition.

Other ingredients may be added to the blend for the purpose ofstabilizing and plasticizing the film.

A bulk filler agent may be present, especially in pullulan free ediblefilm compositions, to modify texture of the compositions. The effectiveamount of the bulk filler agent can range from approximately 10% toabout 90%.

Pullulan free edible film compositions can include an effective amountof carageenan, microcrystalline cellulose and polyethylene glycol. Toenhance the structure of the formed film, hydroxyethyl cellulose can beincorporated.

Useful binding agents include starch, casein and pullulan in amounts upto about 0 to about 10 wt %.

Useful thickening agents include, but are not limited to, celluloseethers, such as hydroxyethyl cellulose, hydroxypropylmethyl cellulose,or hydroxypropyl cellulose, either alone, or mixtures thereof. Otheruseful thickening agents include methylcellulose, carboxylmethylcellulose, and the like, in amounts up to about 20 wt %. Polymersare also useful thickeners, such as carbomer, polyvinyl pyrrolidone,carboxymethyl cellulose, polyvinyl alcohol, sodium alginate,polyethylene glycol, natural gums like xanthan gum, tragacantha, guargum, acacia gum, arabic gum, water-dispersible polyacrylates likepolyacrylic acid, methylmethacrylate copolymer, carboxyvinyl copolymers.The concentration of a water-soluble polymer in the final film can be asdesired or can vary between 20 and 75% (w/w).

A bulk filler agent may be added to the film forming agent for manypurposes, including modifying the texture of the compositions. Theeffective amount of the bulk filler can vary, and can range fromapproximately 10% to about 90% by dry weight of the film composition.Suitable bulk filler agents include, but are not limited to, magnesiumcarbonate; calcium carbonate; calcium phosphate; calcium sulfate;magnesium silicate; aluminum silicate; ground lime stone; clay; talc;titanium dioxide; microcrystalline cellulose; cellulose polymers such aswood; derivatives thereof; and combinations thereof.

To improve flexibility and reduce brittleness of the edible filmcompositions, a softener or plasticizing agent, may be used. Theeffective amount of the plasticizing agent of the present invention canvary up to about 20% dry weight of the film composition.

There are limitations to the amount of the plasticizer that can be usedin the film. When excessive plasticizer is employed, the film loosesstructural integrity, becomes too flimsy and significantly, becomessticky such that it tends to adhere to other strips of film in thepackage forming a block. This is especially true when the strips arestacked in a vial, which is a preferred form of primary packaging. Ingeneral, from about 0 to about 50 percent plasticizer may be present,preferably form about 0 to about 15 percent. In multi-layer films, theamount of plasticizer present may vary in each film layer.

Suitable plasticizing agents of the present invention include, but arenot limited to, polyols such as sorbitol; glycerin; polyethylene glycol;propylene glycol; monoacetin; diacetin; triacetin; hydrogenated starchhydrolysates; corn syrups; derivatives thereof; and combinationsthereof. A polyalcohol may be used to achieve the desired level ofsoftness of the film. Examples of polyalcohols include glycerol,polyethylene glycol, propylene glycol, glycerol monoesters with fattyacids or other pharmaceutically used polyalcohols. The concentration ofthe polyalcohol in the dry film may range between 0.1 and 5% (w/w). Someplasticizers are water soluble and are miscible with a polymer.

Some suitable plasticizers for oral-mucosal contact and other use inbody cavities include glycerin, sorbitol, any of the glycols,polysorbate 80, triethyl titrate, acetyl triethyl titrate, and tributyltitrate.

Surfactants may optionally be included in the films. Useful surfactantsinclude mono and diglycerides of fatty acids and polyoxyethylenesorbitol esters. When a combination of surfactants is used, the firstcomponent may be a polyoxyethylene sorbitan fatty acid ester, while thesecond component may be a polyoxyethylene alkyl ether or apolyoxyethylene castor oil derivative. Other surfactants include fattyacid ester, pluronic acid, sodium lauryl sulfate, and the like. Thetotal concentration of surfactants in the final film depends on theproperties of the other ingredients, but may stay between 0.1 and 5%(w/w).

Useful stabilizing agents include xanthan gum, locust bean gum andcarrageenan, in amounts ranging from about 0 to about 10 wt % orotherwise. Other suitable stabilizing agents include guar gum and thelike.

If desired, an emulsifier may be included in the film. An emulsifier maybe desired if the film includes oily components which normally would notmix with the water component used in making the film. Emulsifiers mayimprove manufacturability and consistency of the film. Exampleemulsifying agents include casein, triethanolamine stearate, quaternaryammonium compounds, acacia, gelatin, lecithin, bentonite, veegum, andthe like. Amounts typically range from about 0 to about 5 wt % orotherwise.

In addition to the film forming components other components are added toprovide benefits to the user. “Other components”, for the purposes ofthis application, include ingredients that are added to the film for thepurpose of being delivered to the site or use and which are not added tothe ingredients used in forming the film for the purpose of modifyingthe characteristics of the film itself. Other components includes“active components”, “inactive components”, “volatile components” and“volatile active components” within the scope of its meaning.

“Active components” for the purpose of the application, includeingredients that react with the site of application when appliedthereto. “Inactive components” are components that provide a barrier orcovering to the site of application but do not react with theapplication site. “Volatile components” are components that evaporateunder ambient conditions. “volatile active components” are componentsthat are both active and volatile.

The other components must be compatible with the film matrix but mayotherwise range widely. The other components may be fragrance or flavorcomponents, they may be emollients or other dermatological agents, theymay be pharmacologically active agents, or pesticides, herbicides,spermacides or other active agents.

The water soluble films may be applied to inanimate objects, such ascounter tops, floors, bathroom fixtures or they may be applied to animalor vegetable surfaces, such as plant leaves for depositing a leaf shineor pesticide product or to animal fur as a flea preventative. Many ofits most important uses are for application to human beings throughdermal, transdermal, bucal or mucosal means.

The films are useful for dermal application of dermatological orcosmetic substances, such as skin emollients, fragrances or lip or skincolorants, including UV protectants and artificial bronzers. Aparticularly important use is as an antiseptic for open wounds providingan easy method of immediately cleansing the wound surface prior toapplication of a protective covering.

Any agents that improve or treat skin when applied topically may beeasily and inexpensively added to the thin film composition. Theseagents may include, for example, nutrients such as vitamins, minerals,amino acids, anti-oxidants, sunscreen agents, or one or more skinpeeling compounds (e.g., alpha-hydroxyisobutyric acid). Additionally,one or more preservatives (e.g., isobutylparaben) or fragrances may alsobe added to the composition.

Examples of other materials having skin improvement activity includeallantoin, aloe extract, ginseng extract, placenta extract, bovine bloodfreed of protein, and fermentation metabolites.

Examples of the materials having the activity to inhibit peroxide lipidare a hydroxy acid, vitamin A, β carotene, vitamin B₁₂, vitamin E,pigments such as dimethylaminostyryl heptyl methyl thiazolium iodide andplatonin, scutellaria root, rutin, sesame extract and tea extract. Asthe cell activators, Quaternium-45, glycolic acid, γ amino acid, sialicacid, royal jelly, and ginseng extract, etc. are known.

Known cell activators also include materials which promote collagensynthesis and materials having the activity to improve the skin.Examples of such materials include ascorbic acid, various growth factorssuch as transforming growth factor β1, platelet-derived growth factor,fibroblast growth factor and insulin-like growth factor 1, and silkprotein.

A viscosity-enhancing agent, such as carboxymethylcellulose or aderivative thereof or polyacrylic acid polymer in a concentration ofabout 0.1% to about 2% by weight may also be added to the aqueouscomposition.

Color additives, foundations, moisturizers and skin treatments may beincorporated into rapidly dissolving films for use in applying unitdosed applications of cosmetic colorants, foundations, moisturizers andskin treatments to various parts of the face and body, including, butnot limited to, the eyes, lips, hands, and face.

The colorants, foundations, moisturizers and treatments, which may beincorporated into the film delivery system, include, but are not limitedto iron oxides, mica, alpha hydroxy acids, beta hydroxy acids, TiO2 andmica, polymethyl methacrylate [beads], salicylic acid, and benzoylperoxide.

The film may be used to deliver the active ingredient or cosmetic byseveral different techniques depending on the specific film and activeor cosmetic ingredient.

In one embodiment, the film is utilized by dissolving with sufficientamounts of water to form a smooth spreadable composition of a slurry orcream like consistency and smoothing the composition onto the user'sskin.

The films are useful for transdermal delivery of active ingredients.

The films are useful for bucal administration of flavorants, mouthfresheners, and oral antiseptics. In one important application they areuseful for the delivery of unit doses of pharmacologic agents.

The films are useful for mucosal administration of vaginal deodorants,fragrances, pH modifiers, spermacides, hemorrhoidal anti inflammatoriesor pharmaceutically active agents.

In other embodiments, the film is striped with different side-by-sideformulations, or layered with distinct film formula laminations.

The amount of active ingredient that can be contained in a thin film islimited by a number of constraints, primary among those being filmthickness, strip size, solubility, brittleness and curling.

More than one flavor may be present in a film. This can be accomplishedtwo ways: First, by using multiple feed streams of differently flavoredfilms when manufacturing the films; and second, by having amultiple-layer film with each layer of a different flavor. In the lattercase, the film can be co-manufactured, or can be bonded together with awater soluble edible binder. For example, one layer can be caramelflavored and the other layer can be chocolate flavored. As anotherexample, a single layer film can be striped with alternating layers thatare cherry flavored with a red color and vanilla flavored with a whitecolor.

The flavorings that can be used include those known to the skilledartisan, such as natural and artificial flavors. These flavorings may bechosen from synthetic flavor oils and flavoring aromatics, and/or oils,oleo resins and extracts derived from plants, leaves, flowers, fruitsand so forth, and combinations thereof. Representative flavor oilsinclude: spearmint oil, cinnamon oil, peppermint oil, clove oil, bayoil, thyme oil, cedar leaf oil, oil of nutmeg, oil of sage, and oil ofbitter almonds. Also useful are artificial, natural or synthetic fruitflavors such as vanilla, chocolate, coffee, cocoa and citrus oil,including lemon, orange, grape, lime and grapefruit and fruit essencesincluding apple, pear, peach, strawberry, raspberry, cherry, plum,pineapple, apricot and so forth. These flavorings can be usedindividually or in admixture. Commonly used flavors include mints suchas peppermint, wintergreen, spearmint, birch, anise and such fruitflavors, as cherry, lemon-lime, orange, grape, artificial vanilla,cinnamon derivatives, and others, whether employed individually or inadmixture. Flavorings such as aldehydes and esters including cinnamylacetate, cinnamaldehyde, citral, diethylacetal, dihydrocarvyl acetate,eugenyl formate, p-methylanisole, and so forth may also be used.Generally, any flavoring or food additive, such as those described inChemicals Used in Food Processing, publication 1274 by the NationalAcademy of Sciences, pages 63-258, may be used.

Further examples of aldehyde flavorings include, but are not limited toacetaldehyde (apple); benzaldehyde (cherry, almond); cinnamic aldehyde(cinnamon); citral, i.e., alpha citral (lemon, lime); neral, i.e. betacitral (lemon, lime); decanal (orange, lemon); ethyl vanillin (vanilla,cream); heliotropine, i.e., piperonal (vanilla, cream); vanillin(vanilla, cream); alpha-amyl cinnamaldehyde (spicy fruity flavors);butyraldehyde (butter, cheese); valeraldehyde (butter, cheese);citronellal (modifies, many types); decanal (citrus fruits); aldehydeC-8 (citrus fruits); aldehyde C-9 (citrus fruits); aldehyde C-12 (citrusfruits); 2-ethyl butyraldehyde (berry fruits); hexenal, i.e. trans-2(berry fruits); tolyl aldehyde (cherry, almond); veratraldehyde(vanilla); 2,6-dimethyl-5-heptenal, i.e. melonal (melon);2-6-dimethyloctanal (green fruit); and 2-dodecenal (citrus, mandarin);cherry; grape; mixtures thereof; and the like.

The amount of flavoring employed is a matter of preference subject tosuch factors as flavor type, individual flavor, and strength desired.Thus, the amount may be varied in order to obtain the result desired inthe final product. Such variations are within the capabilities of thoseskilled in the art without the need for undue experimentation. Ingeneral, amounts of about 0.1 to about 30 wt % are useable with amountsof about 2 to about 25 wt % being useful and amounts from about 3 toabout 7 weight percent may be more useful.

Suitable sweeteners that can be included are those well known in theart, including both natural and artificial sweeteners.

Water-soluble sweetening agents such as monosaccharides, disaccharidesand polysaccharides such as xylose, ribose, glucose (dextrose), mannose,galactose, fructose (levulose), sucrose (sugar), maltose, invert sugar(a mixture of fructose and glucose derived from sucrose), partiallyhydrolyzed starch, corn syrup solids, dihydrochalcones, monellin,steviosides, and glycyrrhizin may be used.

Water-soluble artificial sweeteners such as the soluble saccharin salts,i.e., sodium or calcium saccharin salts, cyclamate salts, the sodium,ammonium or calcium salt of3,4-dihydro-6-methyl-1,2,3-oxathiazine-4-one-2,2-dioxide, the potassiumsalt of 3,4-dihydro-6-methyl-1,2,3-oxathiazine-4-one-2,2-dioxide(acesulfame-K), the free acid form of saccharin, and the like may beused.

Also useful are dipeptide based sweeteners, such as L-aspartic acidderived sweeteners, such as L-aspartyl-L-phenylalanine methyl ester(aspartame) and materials described in U.S. Pat. No. 3,492,131,L-alpha-aspartyl-N-(2,2,4,4-tetramethyl-3-thietanyl)-D-alaninamidehydrate, methyl esters of L-aspartyl-L-phenylglycerin andL-aspartyl-L-2,5,dihydrophenyl-glycine,L-aspartyl-2,5-dihydro-L-phenylal-1-anine,L-aspartyl-L-(1-cyclohexyen)-alanine, and the like.

Water-soluble sweeteners derived from naturally occurring water-solublesweeteners, such as a chlorinated derivative of ordinary sugar(sucrose), and protein based sweeteners such as thaumatoccous danielli(Thaumatin I and II).

Other sweeteners may be used as well.

The disclosed films solve the problems associated with high loadings ofactive ingredients by laminating multiple layers of thin films to oneanother, where the films have physical and/or chemical properties whichare modified depending on the function that layer plays in the laminatestructure. Thus, higher loading may be provided in inner layers with theouter layers having lower loadings or even no actives present. Ingeneral the mount of actives that may be utilized ranges from 0 to 70percent by weight. In most cases it is preferred to limit the amount ofactives to less than twenty percent.

This disclosure provides for the use of multiple layers to increaseactive loading significantly beyond current single or bi-layer films. Ingeneral, there may be any number of layers of film in excess of two. Formost applications, 3 to 5 layer laminates will provide the expectedbenefits.

The thickness of the single or multi-layer films can vary widely. It ispreferably that the thickness be in the range of from about 0.25 toabout 12 mils, preferably from about 0.5 to about 2 mils. It should berecognized that multi-layer films will be thicker than single layerfilms.

For example, one preferred embodiment contains a bottom layer with highplasticizer content, a middle layer with a high active loading and a toplayer with high plasticizer content. The resulting film lamination orsandwich remains flat and flexible even if the middle layer becamebrittle.

Where multiple active ingredients are desired, each may reside in itsown laminate layer having different physical or chemical properties.Where two active ingredients are inter-reactive, the separate layerswill significantly extend the shelf life of the product or even allowthe development of new products by preventing interaction until utilizedby the customer or patient.

A further embodiment anticipates that one or more of these layers mayalso contain air bubbles that increase surface area for improveddissolution.

These films can be manufactured individually and the multiple layerscombined after manufacture but in a preferred embodiment the films aremanufactured simultaneously. The simultaneous manufacturing processrequires the selection of thin films that have the correct rheology sothat they don't merge into one another during the manufacturing process.

Exemplary coating methods are a slot die for up to 3 layers of filmslurries that have a viscosity range of approximately 15 Cp to 20,000Cp, or a slide coater for up to 18 layers of film slurries with aviscosity range of approximately 1 Cp to 500 Cp.

Other coating methods could be used with coating layers that are notcoterminous.

The film is adapted to have a low tensile strength so that it dissolvesreadily when placed in a high moisture environment such as the mouth,for example. The film 12 is generally formed by coating a film formingslurry 6 on a surface of a suitable substrate 14 and drying the filmforming slurry 6 on the substrate 14. In one embodiment, a drying oven13 can be used to dry the slurry 6. After drying, the substrate 14 canbe delaminated from the dried coating or film 12. In an alternateembodiment, the substrate 14 can be delaminated from the coated slurry 6after the coating stage. After drying, the dried film 12 can then be cutinto strips 8 for subsequent packaging.

The slurry 6 generally comprises a mixture of film forming ingredients.During the coating stage, the slurry 6 is cast or coated onto thesubstrate 14. In one embodiment, a slot die is used to coat the wetslurry 6 onto the substrate 14. In alternate embodiments any suitablefilm forming coating or casting system can be used to coat the wetslurry onto the substrate, including for example, a knife over rollsystem. It is a feature of the present invention to be able to coat theslurry 6 onto the substrate 14 with a degree of accuracy wherein thethickness of the film forming slurry 6 is not dependent upon thethickness of the paper or substrate 14. In the preferred embodiment, theslot die can sit approximately 10 millimeters above the paper. The moreslurry that is pumped, the more slurry that is coated onto the paper.

In one embodiment, the substrate 14 is a liner-backed paper stock. Thesubstrate 14 can include a coating 1,3 on each side of the substratethat allows the slurry 6 or film 12 to be readily separated from thebacker substrate 14, while still maintaining adequate surface tension.The coating 1 on one side of the substrate 14 is generally adapted toprovide adequate surface tension to allow the film forming slurry 6 tospread out on the substrate as well as bond to the substrate 14. Thecoating 1 must also be able to provide sufficient release ability toallow the dried film 12 to be removed from the substrate 14. The coating3 on the other side of the substrate 14 is generally adapted to allowthe substrate 14 and film 12 to be rolled onto itself without anyadhering effects. The coating 1, 3 on the backing substrate or paper 14provides versatility and advantages over the properties of a heat beltor continuous web.

Referring to FIG. 2, an illustration of a wet film forming slurry 21 isshown coated or cast onto the substrate 22. In this embodiment, thesubstrate 22 comprises a liner-backer that is coated on both sides 23,24. One side 23 is coated with for example, a silicone. The film formingslurry 21 is cast or coated onto the polyethylene side 23 of thesubstrate 22. In alternate embodiments, the substrate can include anysuitable coating material that allows the film forming slurry 21 torelease from the substrate 22 after it is dried as well as allow theside 23 of the substrate 22 coated with the film forming slurry 21 to berolled onto itself.

Referring to FIG. 2, the polyethylene coating 23 on the substrate 22enables the film forming slurry 21 to spread out over the polyethylenesurface of the substrate. The film forming slurry 21 is coated or castonto the polyethylene side 23 of the substrate 22 in a wet form. Thepolyethylene surface 23 provides the film forming slurry 21 with asurface that it can bond to, but still provides a “release ability” thatenables the film forming slurry fibers to be relatively easily removedafter further processing. The surface tension of the polyethylenesurface 23 allows the film forming slurry 21 to remain relatively flatas the slurry 21 is coated onto the substrate, but the surface tensionis not too much to keep it from coming off or being removed duringsubsequent processing. The relationship of the paper or substrate 22 tothe slurry 21 is important to the overall process.

Referring to FIG. 1, after the film forming slurry 6 has been coatedonto the substrate 14, the combination of the substrate 14 and slurry 6is passed through a drying oven 13. The drying oven 13 is generallyadapted to dry the slurry 6 while retaining the flavor content of theslurry 6 in the film 12 formed by the drying process. Although a dryingoven 13 is shown and described, any suitable drying device can be usedthat is adapted to dry a film forming slurry while retaining volatileactive components in the resulting product. It is a feature of thepresent invention to minimize the amount of volatile active components“flashed” off the drying slurry.

The drying oven 13 generally comprises a through drying oven that isadapted to heat and dry the film forming slurry 6 at relatively lowtemperatures and low speeds. In one embodiment, the drying oven 13 is amultizone reflow oven in which the drying temperature can be varied inevery zone. The drying temperatures in the oven 13 can be “ramped up”slowly as substrate with the film forming slurry thereon travels throughthe oven.

The amount of air flowing through the oven is recirculated in order tokeep volatile active components in the ambient environment.Approximately 70% of the air can be recirculated in order to assist inretaining the volatile active components in the resulting film 12. Thecombination of drying at low temperatures and low speeds andrecirculating air, helps in minimizing the amount of volatile activecomponents that are flashed off during the drying process. Bymaintaining a certain amount of volatile active components in theambient environment during drying, more volatile active components areretained in the resulting dried film 12.

As shown in FIG. 1, the system 10 can further include one or moremoisture meters 4. The moisture meter 4 is generally adapted to measurea moisture content of the film 12 as it exists in the oven 13. inalternative embodiments, especially where the drying apparatus containsdifferent temperature zones, multiple moisture meters are used atvarious point in the drying line. In one embodiment, the moisture meter4 comprises an inline, infra-red moisture meter. In alternateembodiments, any suitable moisture detection system can be used todetermine moisture content of a film. It is a feature of the presentinvention to continuously monitor a moisture content of the film 12 asit dries within the apparatus and/or as it exists in the drying oven 13and control a speed and/or temperature [especially in a multiple zonedryer] of the drying process on the basis of the measured moisturecontent. In one embodiment, the inline moisture meter 4 traverses theweb of the film 12 as it exits the drying oven.

For manufacturing and production purposes the film 12 should not be toowet or dry. In one embodiment, the residual moisture content of the film12 as it exists in the drying oven 13 should be in the range of fromabout 5 to about 30, preferably from about 11 to about 23 and mosttypically approximately 16-19% of water content by weight.

In alternate embodiments, any suitable residual moisture content can beused that achieves a desired product. It is a feature of the presentinvention to correlate the measured residual water content of the driedfilm to the speed of the substrate 14 and web as it passes through thedrying oven 13. For example, if the residual moisture content reading ishigher than desired, the controller 2 is adapted to adjust the speed ofthe web so that more time is spent traveling through the drying oven.

In one embodiment, the controller 2 could also adjust the temperature(s)of the zone(s) of the oven 13 to adapt for the differences between adesired and the measured residual moisture content. For example, if themeasured residual moisture content is too low, the temperatures in thevarious zones could also be reduced. The controller 2 receives themeasured moisture content and then determines whether or not to changethe speed of the web and/or change the temperature of the oven.

As shown in FIG. 1, the backing substrate 14 is generally fed into thecoating stage from a roller 11. The backing substrate 14 can have awidth of any suitable dimension. The width of the substrate 14 is alsoreferred to herein as a “web”. The coating device 15 coats the filmforming slurry onto the substrate 14. As shown in FIG. 1, in oneembodiment, the backing paper 14 a can be delaminated after the coatingstage and rolled onto roll 18 a. The film-forming slurry 6 is then driedin the drying oven 13 to form the film 12.

After the film 12 is dried, the backing substrate 14 and film 13 isrewound on itself onto a roll 16. As shown in FIG. 2, the silicon layer24 of the substrate 22 is wound on top of the dry coating. The roll 16can then be cured for a desired period of time. In one embodiment, theroll 16 can be placed in a foil bag that acts as a barrier tosubstantially reduce or minimize the evaporation of moisture from thefilm 12, as well as minimize the flashing of flavor. The roll 16 couldbe kept in the foil bag for any suitable period of time to complete thecuring process, typically 2 to 5 days, most typically approximately fourdays.

After the roll 16 has cured for a suitable length of time, the film 12can be converted. This includes cutting and packaging the film 12. Asshown in FIG. 1, in one embodiment where the substrate 14 has not beendelaminated, the roll 16 is unwound and the substrate 14 is delaminatedfrom the dried film 12. The substrate 14 can be rewound into a roll 18.The film 12 then travels through a cutting device 19 that cuts the webof film into any suitable number of strips along a length of the web.Each strip is then cut to a desired length to form the segments 8. Thesegments 8, also called strips, can then be packaged for distribution.

One embodiment of a converting or cutting process is described withreference to FIG. 3. As the film 12 comes off or away from the liner 14,the film 12 passes over a cutting device 31. The cutting device 31generally comprises a series of slitters that slit or cut the film orweb 12 into strips along the direction of travel 33 of the web. Tensioncontrol devices and static control devices (not shown) are used tomaintain the composition of the web.

Referring to FIG. 4, another embodiment of a converting process isillustrated. As shown in FIG. 4, the cured roll 41 of material inunwound. The backing substrate can be rewound onto a material unwindroll 42. The coated web 12 then proceeds over the slitter 43. Theslitter 43 generally comprises a series of cutting devices. In oneembodiment, the slitter 43 comprises a device having a twenty-fiveslitters 49, although any suitable number of cutting devices can beused. Each individual slitter 49 cuts the web 12 along the direction oftravel of the web flow 40. In the example shown in FIG. 4, after the web12 passes through or over the slitter 43 and is cut, twenty-fourseparate film strips or lanes 45 are formed. The edge trim selvage 47can be discarded.

The twenty-four strips 45 travel through a cutting device 44. In oneembodiment, the cutting device 44 comprises a guillotine shear. Thecutting device 44 is generally adapted to cut each strip 45 into smallerpieces or segments, such as segments 8 shown in FIG. 1. Generally, anysuitable cutting device 44 can be used to cut the film strips 45 intothe small pieces 8. It is a feature of the present invention to cut thefilm strips 45 into a size that is adapted to be inserted into themouth, for example on or under the tongue.

After the web 12 is slitted, each strip 45 is pulled over a turnbar 46.Approximately one-half of the strips 45 can be pulled towards one side51, while the other half can be pulled toward the other side 52. Thestrips 45 are pulled and make an approximately 90° turn around theturnbar 46. A gripper 53 is adapted to grip a top and bottom of eachstrip 45 and pull the strip 45 in approximately 1¼ inch increments.After the strips 45 are moved into position by the gripper, a guillotinecut is made. Each cut results in twelve pieces of the film strips 45formed at each cut at each side of the turn bar 46. When a predeterminedamount of cuts are made, such as for example twelve, the pieces 8 ofFIG. 1 are pushed into a stack. The stack can then moved into a cassettebase.

In one embodiment, referring to FIG. 5, two rolls 51, 52 of cured filmcan be converted at the same time, one on top of the other. If notalready delaminated, the backing substrate 57, 59 from each roll 51, 52can be delaminated and rolled onto rolls 53, 55. The two webs 55, 56 ofthe formed film can then be processed in the slitting stage 60 and thecutting stages 61. In this fashion, 24 strips of film can be cut in asingle pass of the guillotine shear 44 of FIG. 4.

Referring to FIG. 6, one embodiment of a system 600 for converting athin film material into small strips is illustrated. The product stripweb and carrier web 602 is placed on an unwind roll 604. The combinationof the product strip web and carrier web 602, which has been cured in aprocess similar to that described with respect to FIG. 2, is unwound offthe roll 604 and fed into a delaminating section 606, where the paperbacking 608 of the carrier web is delaminated from the product strip weband rolled onto a rewind roll 610. The delaminating section 606 isadapted to allow the paper or backing to be peeled away from or off ofthe roll 602. In one embodiment of the invention the delaminatingsection 606 comprises a dancer including a counterweight 616 that allowstension to be applied to the backing paper 608 and not the product strip614. The product strip 614 can be looped down and across to the splicingtable 620.

The full sheet 614 is fed onto the splicing table 620 and into a cutter622, where the sheet 614 is cut or slit lengthwise into strips. In oneembodiment, the cutter 622 can comprise a DOSENBURY CRUSH CUT KNIFEASSEMBLY, although any suitable knife assembly can be used. As shown inFIG. 7, the knife assembly 622 preferably comprise a series oftwenty-five slitters to slit the full sheet into twenty-four strips 624,each approximately ⅞″ wide (______ mm). Although the strips aredescribed as being approximately ⅞″ wide, the strips 624 can be anysuitable dimension. The outer strips 710, or selvage, can be discarded.

Referring to FIG. 7, the strips 624 are then pulled or directed over aturn bar assembly 628. The turn bar assembly 628 generally comprises aseries of bars over which each strip 624 is directed. Each turn bar isangled at approximately 45°, which allows each strip 624 to loop overthe bar and turn approximately 90°. This allows each strip 624 to bepositioned one on top of another. In one embodiment, where the productweb 614 is slit into twenty-four strips, all twenty-four strips can bestacked. In an alternate embodiment, the turn bars can be positioned sothat where twenty-four product strips are available, two rows of twelvestrips each are formed or one row of twenty-four.

A shear 626 is adapted to cut across a width of each slit strip 624. Theshear or knife assembly 626 cuts each stack of strips 624 into segments,such as for example, one-inch (2.54 cm) segments. The segments, eachhaving a plurality of one-inch product strips can then be packaged.Where twenty-four strips have been turned on top of each other, a stackof twenty-four, one-inch segments will be formed. The segments 714 shownin FIG. 7 are then moved along a conveyor 718 and deposited intosuitable sized containers 722, such as for example a cassette. Thecontainers 722 can then be transported to a labeler or other sortableprocessing station.

In one embodiment, the product web 614 is slitted into a series ofstrips 624. The strips 624 are looped down and then up across each turnbar in the turn bar assembly 628. A clamp device can be used to clampthe strip while the knife cuts the strip.

It should be understood that the foregoing description is onlyillustrative of the invention. Various alternatives and modificationscan be devised by those skilled in the art without departing from theinvention. Accordingly, the present invention is intended to embrace allsuch alternatives, modifications and variances which fall within thescope of the appended claims.

1. A lightweight product composed of a mixture of film formingingredients and other components manufactured by a method comprising:coating a liner substrate with a wet slurry of the mixture of filmforming ingredients and other components; drying the wet slurry in adrying oven to form a film; measuring a moisture content of the film asthe film exists in the drying oven; and storing the film in a minimalmoisture loss environment during a curing process where the lightweightproduct is in the form of a sheet comprising at least one layer whereeach of the at least one layer comprises at least one solid polymerselected from low-temperature-melt polymers and liquid soluble polymers,such polymer having at least one other component dispersed throughoutthe polymer matrix.
 2. The lightweight product of claim 1 where thepolymer is at least one solid low temperature melt polymer.
 3. Thelightweight product of claim 1 where the polymer is at least one liquidsoluble polymer.
 4. The lightweight product of claim 3 where the polymeris at least one water soluble polymer.
 5. The lightweight product ofclaim 1 comprising at least two polymers.
 6. The lightweight product ofclaim 1 where the polymers are in the form of a laminated film whereeach layer of the laminate contains a cosmetic or skin care activecomponents and the cosmetic or skin care active components are selectedfrom the same and different cosmetic or skin care active components. 7.The lightweight product of claim 6 where the laminated film containslayers laminated on top of each other.
 8. The lightweight product ofclaim 6 where the laminated film contains layers laminated side by side.9. A lightweight cosmetic or skin care product composed of a mixture offilm forming ingredients and other components and prepared by coating aliner substrate with a wet slurry of the mixture of film formingingredients and other components; drying the wet slurry in a drying ovento form a film; measuring a moisture content of the film as the filmexists in the drying oven; and storing the film in a minimal moistureloss environment during a curing process where the lightweight productcomprises dehydrated or encapsulated cosmetic or skin care activecomponents dispersed within the matrix of a liquid soluble film formingpolymer.
 10. The product of claim 9 combined with sufficient liquid todissolve the film forming polymer and release the cosmetic or skin careactive components.
 11. The product of claim 10 where the liquid iswater.
 12. The product of claim 1 where the thickness of the film is inthe range of from about 0.25 to about 12 mils.
 13. The product of claim1 where the thickness of the film is in the range of from about 0.5 toabout 2 mils.
 14. The lightweight product of claim 18 comprising onelayer.
 15. The lightweight product of claim 1 where the other componentis an active component.
 16. The lightweight product of claim 1 where theother component is a volatile active component.
 17. The lightweightproduct of claim 1 where the other component is an inactive component.